Projectile acceleration arrangement



Jan. 20, 1910 A. A. LAVINE 3,490,372

PROJECTILE ACCELERATION ARRANGEMENT Filed NOV. 9, 1966 3 Sheets-Sheet lA. A. LAVINE PROJECTILE ACCELERATION ARRANGEMENT Jan. 20, 1970 3Sheets-Sheet 2 Filed Nov. 9, 1966 US. Cl. 10224 9 Claims ABSTRACT OF THEDISCLOSURE There is described in this patent application an explosiveconfiguration in which a first high explosive charge member and a secondhigh explosive charge member are combined to provide a constant angleMach stem for the acceleration of a projectile or generation of a shapedcharge. The first high explosive charge member has a detonation frontvelocity that is always greater than the detonation front velocity inthe second high explosive charge member. The constant angle Mach sterngenerated in the second high explosive charge member provides aconstantly increasing momentum for acceleration of a projectile orgeneration of a jet in a shaped charge.

This invention relates to the projectile art and more particularly to animproved means for accelerating a projectile to a very high velocity.

In many applications it is often desirable to accelerate a projectile,or other structure, to a very high velocity. Such applications, ofcourse, include projectiles accelerated by high explosives as may befound in conventional ammunition, hypervelocity particle study, and heatgeneration studies obtained from the impact of high velocityprojectiles. It will be appreciated that applicant uses the wordprojectile to encompass all forms of structure that may be acceleratedby the techniques described herein and is not to be construed aslimiting to any type or class of such structure.

While various techniques utilizing high explosives for providing highprojectile velocities have heretofore been proposed, the maximumvelocities actually achieved in such prior art arrangements have been onthe order of 10,000 feet per second. Such arrangements have oftenutilized a high explosive in which there is generated a variable angle(Mach stem) as disclosed, for example, in The Science of HighExplosives, by Melvin A. Cook, 1958, Reinhold Publishing Corporation,New York, NY. However, a variable angle Mach stern utilized in thesehigh explosive techniques has not been able to provide the ultra-highprojectile velocities in the above-mentioned applications wherein it isoften desired to have projectile velocities on the order of 40,000 ormore feet per second.

Accordingly, it is an object of applicants invention herein to providean improved structure for accelerating projectiles.

It is another object of applicants invention herein to provide a highexplosive charge arrangement in which a constant angle Mach stem isgenerated.

It is yet another object of applicants invention herein to provide ahigh explosive charge arrangement in which 'a constant angle Mach stemis generated for accelerating ited States Patent F 3490l37Z PatentedJan. 20, 1970 and the first end of the second cylindrical high explosivecharge member is substantially coplanar with the first end of the firstcylindrical high explosive charge member and the second end of thesecond cylindrical high explosive charge member is spaced from the baseportion of the aperture.

An inert cylindrical member is positioned in the aperture intermediatethe second end of the second cylindrical high explosive charge memberand the base portion of the aperture. The inert cylindrical member is awave shaper to shape a detonation front generated by the ignition ordetonation of the high explosive charge members.

In this embodiment the exterior surface of the second end of the firstcylindrical high explosive charge member is the preselected surfaceportion for ignition thereof to initiate the generation of a detonationfront. The detonation front moves axially along the first cylindricalhigh explosive charge member and is intercepted by the abovementionedwave shaper. The detonation front velocity in the first cylindrical highexplosive charge member is a first predetermined value and thedetonation front velocity in the second cylindrical high explosivecharge member is a second predetermined value less than the first value.

Therefore, as the detonation front passes the wave shaper it generates adetonation front in the second cylindrical high explosive charge member.However, since the detonation front velocity of the second cylindricalhigh explosive charge member is less than the detonation front velocityin the first cylindrical high explosive charge member, the detonationfront converges toward a point along the axis of the second cylindricalhigh explosive charge member at a predetermined angle, and, according tothe principles of applicants invention, this angle is preferablymaintained comparatively small and is constant. This substantiallyconstant, small angle generated by the detonation front in the secondcylindrical high explosive charge member generates a Mach stem ofincreasing momentum comprised of comparatively high density gases. Inthis embodiment of applicants invention, the Mach stem is substantiallyconical in shape because of the symmetrical nature of the secondcylindrical high explosive charge member about its axis.

As the Mach stem traverses the second cylindrical high explosive chargemember, the momentum thereof substantially increases continually untilit reaches the first end thereof.

A projectile which is to be accelerated is positioned on the first endof the second cylindrical high explosive charge member and the effect ofthe high momentum Mach stem on the projectile accelerates the projectileto comparatively high velocities.

In other embodiments of applicants invention there is provided a highexplosive charge means in which a substantially Wedge-shaped Mach stemis generated to provide an arrangement for accelerating an elongatedprojectile.

The above and other objects are understood more completely from thefollowing detailed description taken together with the accompanyingdrawing wherein similar reference characters refer to similar elementsthroughout and in which:

FIGURES 1, 2 and 3 illustrate one embodiment of applincants inventionand the principles of operation thereof;

FIGURES 4 and 5 illustrate another embodiment of applicants invention;

FIGURES 6 and 7 illustrate another embodiment of applicants invention;

FIGURE 8 illustrates another embodiment of applicants invention;

FIGURES 9 and 10 illustrate another embodiment of applicants invention;and

FIGURE 11 illustrates a directed sheet warhead embodiment of applicantsinvention.

It will be appreciated that while applicant has chosen some specificembodiments of his invention for illustration of the techniques forproviding high projectile velocities, such embodiments as illustratedand described herein are not to be construed as limitations upon thebroad concepts of applicants invention. Further, where practical, thestructure and design features illustrated in one embodiment may beequally well used in other embodiments to provide the improvements inhigh projectile velocity structures according to applicants invention.

Referring now to FIGURES 1, 2 and 3, there is shown the structureassociated with one embodiment of applicants invention. As shown inFIGURE 1, there is a projectile accelerator, generally designated 10,comprised of a charge means 12 that, in this embodiment of applicantsinvention, is cylindrical.

The charge means 12 is comprised of a first cylindrical high explosivecharge member 14 and a Second cylindrical high explosive charge member16. An initiator or detonator means 18 which, for example, may beelectrically ignited through source of electrical energy such as battery20 and switch means 22, is utilized to ignite or detonate the chargemeans 12.

The first cylindrical high explosive charge member 14 has walls 24defining an aperture 26 which has a base portion 28. As shown in FIGURES1, 2 and 3, the second cylindrical high explosive charge member 16 ispositioned in the aperture 26 and has a first end 30 that issubstantially coplanar with the first end 32 of the first cylindricalhigh explosive charge member 12 and a second end 34 that is spaced apartfrom the base portion 28 of the aperture 26 and from the second end 36of the first cylindrical high explosive charge member 14.

The detonator 18 is coupled or otherwise afiixed to the exterior surface35 of the second end 36 to provide ignition or detonation of the highexplosive charge means 12 to commence the generation of a detonationfront therefrom.

An inert cylindrical member 38 is positioned intermediate the secondcylindrical high explosive charge member 16 and the base surface 28 ofthe aperture 26 and is a wave shaper to provide the proper shaping ofthe detonation front wave as it traverses through the charge means 12.

A projectile 40 is coupled or otherwise affixed to the second end 30 ofthe second cylindrical high explosive charge member 16 and, for thisembodiment of applicants invention, the projectile 40, the firstcylindrical high explosive charge member 14 and the second cylindricalhigh explosive charge member 16 and the detonator 18 are substantiallycoaxially aligned.

When it is desired to accelerate the projectile 40, according toapplicants invention herein, the detonator or initiator 18 is energizedand this commences the generation of a detonation front from the secondend 36 of the second cylindrical high explosive charge member 14.

This phenomena is more clearly illustrated in FIG- URE 3. As shown inFIGURE 3, the detonation front indicated by the line 42a is traversingthe first cylindrical high explosive charge member 14 in the directionindicated by the arrow 44. As the detonation front 42a is intercepted bythe wave shaper inert cylinder 38, it commences to travel through theannular section of the first cylindrical high explosive charge member14, which surrounds the aperture 26. As the detonation front approachesand impinges upon the peripheral edge 37 of the bottom surface 34 of thesecond cylindrical high explosive charge member, the detonation front isgenerated in the second cylindrical high explosive charge member 16.

The first cylindrical high explosive charge member is selected to have adetonation front velocity that is greater than the velocity of thedetonation front in the second cylindrical high explosive charge member16. As such, a generally conical detonation front is provided in thesecond cylindrical high explosive charge member 16 that has its apexalong the axis 46 as the detonation front moves radially inwardly asindicated by the arrow 48 in the second cylindrical high explosivecharge member 16 and the detonation front 42 moves in the directionindicated by the arrow 44 along the side peripheral wall 50 of thesecond cylindrical explosive charge 16.

Thus, the detonation front 52 moving in the second high explosive chargemember 16 generates a Mach stem 54 symmetrically aligned along the axisthereof that is substantially conical in shape as defined by theconically shaped detonation front 52. The angle generated by thedetonation front 52 is indicated to be the angle equivalent to twice theangle a on FIGURE 3. This is the apex angle of the Mach stem 54. Theangle a is determined by the relative detonation front velocities in thefirst high explosive charge member 14 and the second high explosivecharge member 16.

However, at the intersection, that is the apex of the conical detonationfront 52, the detonation front generates two streams as indicated by thearrows 56 and 58. The arrow 56 is generally moving backwardly withrespect to the direction of movement of the detonation front 52 and thestream indicated by the arrow 58 is moving in the same direction axiallyas the detonation from 52 and the stream indicated by the arrow 58generates the Mach stem 54. It will be appreciated that as the materialin the Mach stem 54 moves in a direction indicated by the arrow 58 alongthe axis 46, the density of the gases contained therein remainssubstantially constant, but greater than behind the detonation front,but the size thereof constantly increases even though the angle aremains constant and therefore when the Mach stem 54 reaches the secondend 30 of the second cylindrical high explosive charge member 14, thereis a comparatively high momentum value associated therewith. This highmomentum value is utilized to move the projectile 40 in a directionindicated by the arrow 60. In the preferred embodiment of applicantsinvention, the width of the Mach stem indicated by the letter w at thesecond end 30 of the second high explosive charge member 16 is greaterthan the diameter of the projectile 40, in order that edge losses whichoccur around the periphery of the Mach stem 54 cannot detract from themomentum exchange between the Mach stem 54 and the projectile 40.

From the considerations heretofore set forth, it can be seen, as shownon FIGURE 3, that the Mach stem is properly defined as the intersectionof the wave fronts in second high explosive charge member 16. That isthe Mach stem commences, in inertial space at the point designated 68corresponding to a point on the axis of the second high explosive chargemember 16 along the base surfaces 37 thereof. From a consideration ofthe velocities involved it will be noted that the detonation wave front42a and 42b in the first cylindrical charge member 14 moves in adirection indicated by the arrow 44 at a first predetermined velocity.The detonation wave front 52 which, in the embodiment shown in FIGURE 3is conical, intersecting and having its apex initially at the point 68,moves in a direction indicated by the arrow 70 with a secondpredetermined velocity less than the first predetermined velocity.However, when the detonation front 52 in the second cylindrical chargemember 16 has moved from the position indicated by 52a to the positionindicated by 521), it has traversed a certain distance indicated by theledger a. In this same time interval, it will be appreciated, that theMach stem has moved from the point 68 to the point 72 a greater distancethan a. Thus, with respect to the inertial space point 68 the Mach stemhas a velocity in the axial direction greater than the detonation frontvelocity in the second cylindrical charge member 16.

As noted above material from the second cylindrical charge member 16flows into the Mach stern in the directions indicated by the arrows 56and 58. That portion moving in the direction indicated by the arrow 58is moving relative to the motion of the Mach stem and has, therefore, atotal greater velocity with respect to the fixed inertial point 68 thanthe Mach stem velocity. Consequently, a Mach stem front 74 is generatedthat extends, in this embodiment of applicants invention, across theconical detonation wave front, as shown on FIGURE 3. The velocity of theMach stem front 74 with respect to the velocity of the Mach stem isgreater and consequently there is a material build up between thedetonation front and the Mach stem front, as indicated at 54. Thedensity of the gases and the portion designated 54 remains substantiallyconstant, but because of the greater velocity of the Mach stern front 74in the direction indicated by the arrow 76, there is a constant increasein the momentum associated with the moving Mach stem.

By the time the Mach stem has moved to the point designated 80 there isa fairly large mass contained within the portion designated 54 and,because of the constantly increasing mass the momentum associatedtherewith is comparatively high and is imparted directly to theprojectile 40 for acceleration thereof in a direction indicated by thearrow 60. Thus, the constant angle Mach stem provides this high momentumportion designated by the numeral 54 for acceleration of the projectile40. It will be appreciated that only with the maintenance of a constantangle Mach stern can the higher momentum associated with the portion 54be achieved. That is, with a variable angle Mach stem there is not theconstant momentum build up necessary to provide the ultra-high velocityimparted to the projectile 40. Thus, while the velocity of thedetonation front 52 and the Mach stem front 74 are substantiallyconstant for a given configuration, the constantly increasing mass inthe portion 54 provides the high momentum that can provide the highenergy for accelerating the projectile 40.

While the above embodiment of applicants invention describe theutilization of a constant angle Mach stem in a cylindricalconfiguration, it will be appreciated that such an arrangement may alsobe utilized with a rectangular configuration to provide a rod projectileaccelerating arrangement. One such embodiment for achieving such a rodprojectile arrangement is illustrated in FIG- URES 4 and 5. As shownthereon, there is a charge means 100 comprised of a first high explosivecharge member 102 in the form of a prism or block. The high explosivecharge member 102 has an upper surface 104 and a lower surface 106 thatare parallel and the sides 108 and 110 thereof as well as the endportions 112 and 114 are also respectively parallel.

The first high explosive charge member 102 has wall portions 116defining a slot therethrough that extends from the upper surface 104towards the lower surface 106, but terminates a predetermined distanceabove the lower surface 106. A second high explosive charge member 120is positioned in the aperture formed by the walls 116 and has itsexternal surfaces coplanar with the corresponding external surfaces ofthe first high explosive charge member 102. An inert prism 122 ispositioned in the aperture defined by the walls 116 of the first highexplosive charge member 102 and is intermediate the base of the secondhigh explosive charge member 120 and the first high explosive chargemember 102. A rodlike projectile that is to be accelerated, designated124, is positioned on the upper surface 126 of the second high explosivecharge member 120. A linear initiator 128 is coupled to the lowersurface 106, which surface 106 defines a preselected surface forignition of the charge means 100 in this embodiment of applicantsinvention, and is substantially aligned to be symmetrical with respectto the first high explosive charge member 102 and second high explosivecharge member 120.

The linear initiator may, for example, be fabricated from a materialsuch as Du Pont deta sheets, a registered trademark of E. I. Du Pout deNemours & Company, Inc. and commonly termed a line wave generator.

When the linear initiator 128 is ignited, in a manner similar to thatdescribed above, a detonation front 130 is generated in the first highexplosive charge member 102 and travels from the lower surface 106thereof until it is intercepted by the wave shaper 122. The wave shaper122 performs the functions similar to the wave shaper means describedabove and, in this embodiment of applicants invention, provides adetonation wave front 132 in the second high explosive charge member120. The wave shaper provides that the detonation wave front 132intersects along a line 134 and thus provides a wedge shaped Mach stem.As the detonation front 132 traverses the second high explosive chargemember 120, there is a constant increase in the mass of the high densitygas contained within the limits defined by the detonation front 132 andthe Mach stem front 134 as it moves in the direction indicated by thearrow 136. Since the detonation front velocity of the detonation front130 in the first high explosive charge member 102 is greater than thedetonation front velocity of the detonation front 132 in the second highexplosive charge member 120, the detonation front 130 constantlyprovides the detonation front 132 as it traverses the first highexplosive charge member 102 in the direction indicated by the arrow 138.When the detonation front 134 reaches the upper surface 126 of thesecond high explosive charge member 120, the rod-like projectile 124 isaccelerated because of the high momentum contained within the constantangle Mach stem. The mechanism of this acceleration is, of course,similar to that described above in connection with FIGURES 1, 2 and 3except that in this embodiment of applicants invention the Mach stemparticles are contained within a wedge shaped configuration rather thanwithin a conical configuration.

Wave shaping may be achieved by means other than an inert cylinder asdescribed above. That is, the configuration and points of ignition ofthe high explosive charge member having the higher of the detonationfront velocities may in itself provide the necessary wave shaping toprovide the constant angle Mach stern. FIGURES 6 and 7 illustrate aprism embodiment wherein rectangular prisms similar to the rectangularprisms described above in connection with the embodiment of FIGURES 4and 5 are utilized; however, a separate wave shaper .means is notprovided, since wave shaping is achieved by the unique points ofapplication of the initiation of the detonation front. As shown onFIGURES 6 and 7 the charge means designated is comprised of a first highexplosive charge member 152 in the form of a rectangular prism having anupper surface 154, a lower surface 156, end surfaces 158 and 160 andside surfaces 162 and 164. The first high explosive charge member 154has walls 166 defining a slot therein extending from the upper surface154 towards the lower surface 156. Contained within the slot defined bythe walls 166 there is a second high explosive charge member 168'. Thefirst high explosive charge member 152 has a higher detonation frontvelocity than the second high explosive charge member 168.

A rod-like projectile to be accelerated designated 170 is positioned onthe upper surface 172 of the second high explosive charge member 168.Thus, this prism configuration of the first high explosive charge member152 and second high explosive charge member 168 and rod-like projectile170 is similar to the charge means 100 described above in connectionwith FIGURES 4 and 5, except that there is not included any separateinert wave shaper such as the wave shaper 122.

The intersection of the lower surface 156 with the side surfaces 162 and164 are the lines upon which the preselected surface portions of thecharge means 150 are ignited and may be ignited simultaneously along theentire length thereof by the linear initiators 174 which may be similarto the linear initiator 128 shown in FIGURES 4 and 5. In this embodimentthey are in the form of triangular sections of Deta Sheet terminating ina point 176 which may be initiated by a detonator or similar means asdescribed above.

When the linear initiators 174 are initiated from the point 176 by thedetonator 178, the detonation front travels linearly therealong andignites the entire line segment defined by the above-mentionedintersection of the lower surface 156 and side surfaces 1'62 and 163 ofthe first high explosive charge member 152. Detonation front then movesthrough the high explosive charge member toward the second highexplosive charge member 168, impinges simultaneously along the lowercorners 180 and 182 thereof. Since the linear velocity of the detonationfront in the first high explosive charge member 152 is greater than inthe second high explosive charge member 168, a constant angle Mach stemis generated and in this embodiment of applicants invention it is alsoin a wedgeshaped form as defined by the intersecting detonation front184 in the second high explosive charge member 168 and the Mach stemfront 186. This moves in the direction indicated by the arrow 188towards the upper surface 172 of the second high explosive charge member168 and upon reaching the surface 172 the high momentum associated withthe material in the constant angle Mach stem accelerates the rod-likeprojectile 170 in a manner described above.

As above described applicants improved constant angle Mach stem has beenshown as utilized to provide acceleration of a projectile. However, itwill be appreciated that applicants invention herein may also beutilized to provide a shaped charge jet. One such embodiment for acylindrical shape charge jet is shown in FIGURE 8. As shown thereonthere is a charge means generally designated 200, comprised of a firstcylindrical high explosive charge member 202 having an upper surface 204and a lower surface 206 and walls 208 defining an aperture thereinextending from the first surface 204 towards the second surface 206.Thus, this first cylindrical high explosive charge member 202 is similarto the first cylindrical high explosive charge member 14 describedabove.

Positioned within the aperture defined by the walls 208 is a tubularsecond high explosive charge member 210 and an inert cylinder 212 at thebase of the aperture defined by the walls 208. A tubular metallic liner212 is positioned within the tubular second high explosive charge member210 and the outer peripheral walls of the tubular metallic liner 212 arecontinuous to the inner peripheral walls 01 the tubular high explosivecharge member 210.

In this embodiment of applicant's invention axial portions of the lowersurface 206 are the preselected surface portions for igniting the chargemeans 200 to provide a detonation front. When these surfaces are ignitedby the igniter 214 in the manner described above, a detonation frontprogresses through the first high explosive charge member 202 from thebottom surface 206 towards the top surface 204. However, in the mannerdescribed above in connection with the embodiment in FIGURES 1, 2 and 3,a detonation front 214 is generated in the second high explosive chargemember 210. It will be appreciated that the detonation front velocity inthe first high explosive charge member 202 is greater than thedetonation front velocity in the tubular high explosive charge member210.

However, in this embodiment of applicants invention, the tubularmetallic liner 212 prevents the intersection of the detonation fronts214, since the tubular second high explosive charge member 210 is not asolid cylinder. However, the detonation fronts 214 intercept with thetubular metallic liner 212 and provide a constant angle Mach stem at theintersection of the detonation front 214 and the metallic liner 212.Thus, there is a Collapsing of the metallic liner 212 to form a jet in amanner analogous to the formation of the typical shaped charge jet.However, in this embodiment of applicants invention the constant angleMach stern as generated by the detonation fronts 214 provide theexceptionally high velocity to be imparted to the particles comprisingthe jet because of the constant increase in the momentum associated withthe particles between the detonation front 214, the Mach stem front 216and the, metallic tubular liner 212. Thus, the jet formed by thecollapsing of the metallic tubular liner 212 is forced outwardly in adirection indicated by thearrow 218 at a comparatively high velocitybecause of the high momentum associated with the small constant angleMach stem.

While the embodiment shown in FIGURE 8 is for a cylindricalconfiguration, it. will be appreciated that a jet may also be providedin a rectangular prism configuration to provide a directed sheet type ofwarhead.

FIGURES 9 and 10 illustrate such an embodiment of applicants invention.As shown on FIGURES 9 and 10 there is a charge means 220 comprised of afirst high explosive charge member 222 in the form of a rectangularprism having substantially parallel top and bottom walls 224 and 226,respectively, substantially parallel side walls 228 and 230,respectively, and substantially parallel end walls 232 and 234,respectively. The first high explosive charge member 222 has walls 236defining a slot therein extending a preselected distance from the uppersurface 224 thereof towards the lower surface 226.

A pair of second high explosive charge members 238a and 23812, which areidentical, are placed in the slot defined by the wall 236 in a spacedapart relationship and a pair of metallic plates 240a and 240k areplaced in a spaced apart relationship against the second high explosivecharge members 238a and 238b, respectively, in a manner indicated inFIGURES 9 and 10. End plates (not shown) may be included if desired toclose the ends of the charge means 220'.

The lower surface 226 of the first high explosive charge member 222contains the preselected surface areas for ignition of v the chargemeans 220. When a wave shaper 242 is provided in the base of theaperture defined by the wall 236 a linear initiator 244 symmetricallyaligns with the first high explosive charge member 222 and second highexplosive charge members 238a and 238b may be utilized in a manneranalogous to that described above in connection with the embodimentshown in FIGURE 4 and FIGURE 5. However, it will be appreciated, thatthe wave shaper 242, which is formed from an inert rectangular prism,may be eliminated and linear initiators similar to those described inconnection with the embodiments shown in FIGURES 6 and 7 utilized toignite the edges 246 and 248 of the first high explosive charge member222 to provide the constant angle Mach stem.

When the charge means 220 is ignited, a constant angle Mach stem isformed in the second high explosive charge members 238a and 238b and isa substantially wedge shaped configuration and collapses the pair ofplates 240a and 24% towards each other to definea directed sheet warheadprovided with a high velocity because of the high momentum associatedwith the material contained within the small constant angle Mach stem.

In all the above embodiments of applicants invention, it will beappreciated, there is provided two different high explosive chargemembers. The first high explosive charge member always has a detonationfront velocity greater than the second'high explosive charge member anda wave shaper which may be the form of an inert object, or in the formof the configuration of the two explosive charge members themselves isutilized to provide the particular detonation front configurationncessary to generate a small constant angle Mach stem. The mechanism ofthe constant angle Mach stem is such that the momentum associated withthe particles contained within the constant angle Mach stem continuallyincreases during the traverse of the constant angle Mach stem throughthe second high explosive charge member. Thus, the increase in momentumprovides a high force for acceleration of a particle or jetdependingupon the configuration.

Applicant has found that HMX, PBX or similar explosives may be utilizedas the first high explosive charge member since they have detonationfront velocities on the order of 8500 to 9000 meters per second.Correspondingly, Comp. B or Comp. C, having detonation front velocitieson the order of 7500 meters per second may be utilized as the secondhigh explosive charge member.

Those skilled in the art may find many variations and adaptations ofapplicants invention. The following claims are intended to cover allsuch variations and adaptations falling within the true scope and spiritof applicants invention herein.

For example, the embodiment illustrated in FIGURE 11 combines thefeatures shown in the embodiment of FIGURES 9 and 10 with the embodimentof FIGURES 6 and 7. Thus, as shown in FIGURE 11, there is anothervariation of the directed sheet warhead embodiment, generally designated250 comprised of a charge means 252 having a first high explosive chargemember 254 and a second high explosive charge member 256. In theembodiment shown in FIGURE 11 the first high explosive charge 252 andsecond high explosive charge 256 are in rectangular prism form, andFIGURE 11 is an end view thereof.

A pair of rectangular metallic plates 258 are coupled to the second highexplosive charge member 256 and are in spaced apart relationship. A lineinitiator 260 is coupled to an external peripheral edge of the firsthigh explosive charge member 254 to provide ignition thereof. The lineinitiators 260 may b efabricated from Detasheet and identical to thelinear initiators 174 shown in FIGURES 6 and 7. The linear initiator 260may be ignited by the detonator 262 to provide detonation of the chargemeans 250.

As described above in connection with FIGURES 9 and 10, a constant angleMach stem is generated in the second high explosive charge member 256 toform a directed sheet warhead from the collapsing metallic plates 258.The charge means 252 may be held together in preferred relationshipshown on FIGURE 11 by any desired sfructural arrangement. The detonationfront velocity in the first high explosive charge member 254 is, ofcourse, greater than the detonation front velocity in the second highexplosive charge member 256.

This concludes the description of applicants invention. What is desiredto be secured by Letters Patent of the United States is:

What is claimed is:

1. In combination:

charge means having preselected surface portions for ignition thereof togenerate detonation front emanating therefrom for travel through saidcharge means for said preselected surface portion;

said charge means comprises:

a first high explosive charge member having a first detonation frontvelocity and having said preselected surface portions thereon;

a second high explosive charge member in detonation relationship to saidfirst high explosive charge member and having a second detonation frontvelocity less than said first detonation front velocity;

means in said charge means intercepting said de tonation front toprovide an intersecting detonation front combination for generating asubstantially constant angle in the intersection of said detonationfront during at least a predetermined portion of the travel of saiddetonation front through said charge means;

said detonation front generates a Mach stem in said charge means andsaid Mach stem having an increasing momentum during said preselectedportions of travel of said detonation front through said charge means;

a projectile means positioned in said charge means to be accelerated bythe material in said Mach stem to regions external said charge means;and

said projectile means is positioned adjacent said second high explosivecharge member.

2. The arrangement defined in claim -1 wherein:

said first high explosive charge member has a pair of spaced apart endsurfaces, and wall portions defining an aperture extending from a firstof said end surfaces into said first high explosive charge member apreselected distance from said first end surface thereof, and saidaperture having a base portion spaced apart from a second end surface ofsaid first high explosive charge member;

said second high explosive charge member is positioned in said apertureand has a first end substantially co-z planar with said first endsurface of said first high explosive charge member and a second endspaced apart from said base portion of said aperture; and

said means comprises a wave shaper means comprising an inert member insaid aperture intermediate said base portion of said aperture and saidsecond high explosive charge member.

3. The arrangement defined in claim 1 wherein said Mach stem defines asubstantially constant angle cone.

4. The arrangement defined in claim 3 wherein:

said first high explosive charge member comprises a first cylindricalhigh explosive charge member having a first end and a second end, andhaving walls defining an aperture extending from said first end towardssaid second end and said aperture having a base portion spaced from saidsecond end of said first high explosive charge member;

said second high explosive charge member comprises a second cylindricalhigh explosive charge member positioned in said aperture and having afirst end substantially coplanar with said first end of said first highexplosive charge member and a second end spaced from said base portionof said aperture;

said wave shaper means comprises an inert cylindrical memberintermediate said base portion of said aperture and said second end ofsaid second cylindrical high explosive charge member;

said preselected ignition surface portions comprise said second end ofsaid first cylindrical high explosive charge member; and

said projectile means is positioned on said first end of said secondhigh explosive charge member.

5. The arrangement defined in claim 1 wherein said Mach stem issubstantially wedge shaped.

'6. The arrangement defined in claim 5 wherein:

said first high explosive charge member comprises a quadrilateral firsthigh explosive charge member having substantially parallel top andbottom surfaces, substantially parallel end surfaces, and substantiallyparallel side surfaces, and walls defining a slot extending from a firstend surface toward a second end surface and extending a preselecteddistance into said first high explosive charge member from said topsurface thereof and said slot having a base portion spaced from saidbottom surface of said first high explosive charge member;

said second high explosive charge member comprises a secondquadrilateral high explosive charge member positioned in said slot insaid first high explosive charge member and having to top substantiallyco-' planar with said top surface of said first high explosive chargemember and a bottom spaced from said base portion of said slot;

said projectile is positioned adjacent said top of said secondquadrilateral high explosive charge member; and

said preselected surface portions for ignition comprise the edgesdefined by the intersections of said sides and said bottom surfaces ofsaid first quadrilateral high explosive charge member.

7. In combination:

charge means having preselected surface portions for ignition thereof togenerate detonation front emanating therefrom for travel through saidcharge means from said pre-selected surface portion;

means in said charge means intercepting said detoation front to providean intersecting detonation front combination for generating asubstantially constant angle in the intersection of said detonationfront during at least a predetermined portion of the travel of saiddetonation front through said charge means; and said charge meanscomprises:

a first cylindrical high explosive charge member having a first end anda second end, and Walls defining an aperture extending axially inwardlya preselected distance from said first end towards said second end, andsaid aperture having a base' portion spaced apart from said second endof said first cylindrical high explosive charge member, and said firsthigh explosive charge member having a first detonation front velocity;

2, second tubular high explosive charge member positioned in saidaperture of said first cylindrical high explosive charge member andhaving a first end substantially coplanar with said first end of saidfirst high explosive charge member, and a second end spaced apart fromsaid base portion of said aperture, and having a second detonation frontvelocity less than said first detonation front velocity;

a tubular metallic liner positioned in said second high explosive chargemember having outer peripheral wall portions contiguous with innerperipheral wall portions of said second tubular high explosive chargemember and said tubular metallic liner extending from said first end tosaid second end of said second tubular high explosive charge member;

said means comprises an inert cylinder member in said aperture of saidfirst cylindrical high explosive charge member intermediate said baseportion thereof and said second end of said second tubular highexplosive charge member; and

said preselected surface portions for ignition comprise said second endof said first cylindrical high explosive charge member.

8. In combination:

charge means having preselected surface portions for ignition thereof togenerate detonation front emanating therefrom for travel through saidcharge means from said preselected surface portion;

means in said charge means intercepting said detonation front to providean intersecting detonation front combination for generating asubstantially constant angle in the intersection of said detonationfront during at least a predetermined portion of the travel of saiddetonation front through said charge means;

said charge means comprises a first high explosive charge member in theform of a rectangular prism,

and having walls defining a slot therein extending a preselecteddistance from a first end thereof towards a second end thereof;

a pair of second high explosive charge members in the form ofrectangular prisms contained within said slot in said first highexplosive charge member in a spaced apart relationship;

a pair of plate means in spaced apart relationship adjacent to said pairof second high explosive charge means;

said preselected surface portions for ignition of said charge meanscomprise edge portions of said base of said first high explosive chargemember;

a pair of linear initiators coupled to said edges of said first highexplosive charge member for initiation of a detonation wave therealong;and

means for detonating said linear initiator.

9. In combination:

charge means having preselected surface portions for ignition thereof togenerate detonation front emanating therefrom for travel through saidcharge means from said preselected surface portion;

means in said charge means intercepting said detonation front to providean intersecting detonation front combination for generating asubstantially constant angle in the intersection of said detonationfront during at least a predetermined portion of the travel of saiddetonation front through said charge means;

said charge means comprises a first high explosive charge member in theform of a rectangular prism, and having walls defining a slot thereinextending a preselected distance from a first end thereof towards asecond end thereof;

a pair of second high explosive charge members in the form ofrectangular prisms contained within said slot in said first highexplosive charge member in a spaced apart relationship;

a pair of plate means in spaced apart relationship adjacent to said pairof second high explosive charge means;

an inert rectangular prism Wave shaper contained within said slot insaid first high explosive charge member;

said preselected surface portions for ignition comprise symmetricalcentralized surface portions of said base of said first high explosivecharge member; and

a linear initiator for initiating a detonation front in said first highexplosive charge member along said preselected ignition surface.

References Cited UNITED STATES PATENTS VERLIN R. PENDEGRASS, PrimaryExaminer US. C X-R,

